Britain had only one colony in mainland South America – a coastal state next to Venezuela that it grabbed from the Dutch more than 200 years ago. This was British Guyana.

By the 1950s, Britain had had enough – and the plan was to hold elections so the Guyanese could take over. But then the man they elected said he was inspired by Soviet Russia. The story of Britain's long exit from Guyana takes in the CIA, MI5, rigged elections and a beautiful American whom JFK considered one of the most dangerous communists in the western hemisphere.

Ros Taylor spoke to historian of Guyana Clem Seecheran, who is the author of Sweetening Bitter Sugar: Jock Campbell, the Booker Reformer in British Guiana 1934-1966, and Rod Westmaas of Guyana Speaks. You can hear Seecheran talking at more length at the National Archives.

Cheddi Jagan's life and work is archived at the Cheddi Jagan Research Centre, which also includes declassified British documents relating to the suspension of the constitution in 1953, from which the readings in this episode were taken. This 1866 history of British Guyana is also interesting. I drew on the National Security Archive's account of the CIA's involvement in British Guyana and on MI5's in The Defence of the Realm: The Authorised History of MI5 by Christopher Andrew,

You can see and hear Cheddi Jagan in the footage from News Room Guyana.

Thanks to Yvonne Singh for suggestions of whom to contact.

Donate to More Jam Tomorrow at Ko-fi.com.

Take our Series Five survey here.

For decades the Security Service did not officially exist. Now it posts on Instagram. But what is MI5? How has it transformed itself since the second world war? And what kind of people work there? Ros Taylor speaks to former Guardian security editor Richard Norton-Taylor and a former legal director of MI5, David Bickford.

Richard Norton-Taylor is the former security editor of the Guardian and the author of several books including The State of Secrecy: Spies and the Media in Britain, and David Bickford, a former legal director of MI5 and MI6 and thriller author – you can get his latest, Cold Protocol, for £5 using the code on his website.

The standard history of MI5 is The Defence of the Realm: The Authorised History of MI5 by Christopher Andrew, which is very long and currently available cheaply on Kindle. Not everyone rated it. Stella Rimington published her autobiography Open Secret, and Eliza Manningham-Buller wrote Securing Freedom.

I also drew on an article by H Dylan, The Intelligence Lobby Before the Intelligence Lobby: MI5 Director General Stella Rimington and the Hunt for the New Legitimacy, Rimington's 1994 Richard Dimbleby lecture and MI5 director Ken McCallum's 2025 threat update,

The account of Anthony Blunt's confession can be found at the National Archives, as can the booklet on Observation.

Margaret Thatcher's Commons statement about Blunt, Tony Blair's response to the 7/7 bombings and footage of the Bishopsgate IRA bombing are available online.

The Imperial War Museum North's exhibition on spies is on until August.

Donate to More Jam Tomorrow at Ko-fi.com.

Dynamic, dreary – Britain has 2,300 miles of motorways, and the country would grind to a halt without these tarmac arteries. But they were part of a fast, futuristic post-war vision. Will we ever build another one?

Ros Taylor talks to Chris Marshall, who runs roads.org.uk, and the musician and comedy writer Jason Hazeley. You can find a special MJT motorway playlist on Spotify, compiled by Jason, Ros, producer David Turnbull and listeners.

Readings are by David Turnbull . Ernest Davies, MP for Enfield, spoke about the need for motorways in 1957 and R Gresham Cooke (Twickenham) discussed speed limits in 1958.

I drew on Motorways (James Drake, H L Yeadon and D I Evans, Faber & Faber, 1969), On Roads (Joe Moran, Profile Books, 2009) and Always a Welcome - the glove compartment history of the motorway service area (David Lawrence, Between Books).

The Motorway Archive contains a vast amount of detail.

The National Express 'Elaine' and Trusthouse Forte ads are on YouTube. The BBC broadcast a documentary in 1969 on The Cost of Motorways. Egon Ronay's service station reviews are available here.

Donate to More Jam Tomorrow at Ko-fi.com.